Method for making a supporting body for the lock of a motor vehicle, and a supporting body thus obtained

ABSTRACT

A method for making a supporting body ( 1 ) for the lock of a motor vehicle, comprises the steps of: forming an intermediate element ( 8 ) made of electrically insulating material provided with conductive paths ( 3 ); setting the intermediate element ( 8 ) inside a mold ( 23 ) for forming the supporting body ( 1 ); and injecting electrically insulating material in the mold ( 23 ) for carrying out co-molding of the supporting body ( 1 ). The intermediate element ( 8 ) and the conductive paths ( 3 ) are made independently, and the conductive paths ( 3 ) are fixed on opposite faces ( 9, 10 ) of the intermediate element ( 8 ) by constraint means ( 15, 16 ) of a mechanical type.

RELATED APPLICATION

This application is a divisional application of U.S. patent applicationSer. No. 10/975,868, filed on Oct. 28, 2004, now U.S. Pat. No.7,591,969.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a method for making a supporting bodyfor the lock of a motor vehicle and to the supporting body obtained bymeans of the method.

2. Description of the Related Art

As is known, a closing system for a door of a motor vehicle basicallycomprises a lock and a striker mounted, respectively, on the door and ona fixed portion of the bodywork in the proximity of the compartment ofthe door itself (or, more rarely, vice versa).

The lock basically comprises a closing mechanism designed to be coupledin a releasable way with the striker to obtain a relative blockingbetween the lock and the striker itself when the door is closed, and acontrol assembly interacting with the closing mechanism and designed toprovide a set of functions, such as, for example, mechanical openingand/or electrical opening and/or remote opening with user identification(passive-entry system), electrical closing, disabling/enabling of theopening of the door from the outside and/or from the inside of the motorvehicle (external-safety and internal-safety or dead-lock functions),and centralized control of the safety functions for all the locks of themotor vehicle via key or remote control.

In order to obtain the functions mentioned above, the control assemblycomprises: a plurality of levers, at least one of which interacts withthe closing mechanism; a plurality of electric motors for the control ofthe aforesaid levers via corresponding mechanical transmissions; aplurality of microswitches for detecting the position of various mobileelements; and an electrical circuit, which connects the microswitchesand the electric motors with an electrical connector, which, in turn,can be connected to the electrical wiring system of the motor vehicle.

The various components constituting the control assembly are generallyhoused in a single supporting body which can be rigidly fixed to thedoor of the motor vehicle and is usually constituted by a shaped casinghaving a thickness smaller than the other dimensions.

The electrical circuit is formed by a plurality of conductive pathsusually obtained by blanking and bending of a strip of metal material,normally copper or brass. In particular, the paths are formed initiallyin a single body, i.e., joined to one another via connecting portions orlinks, and are rendered independent at the moment of fixing of the lockto the supporting body by means of blanking of the aforesaid connectingportions.

The known modalities of fixing of the lock to the supporting body arebasically two.

According to a first possibility, the conductive paths are englobed in aflexible element in the form of a foil (commonly referred to in thesector as “flexfoil”) made of insulating material, generally plasticmaterial, and fixed to the supporting body in a mechanical way, forexample, via riveting.

Alternatively, the conductive paths can be co-molded to the supportingbody of the lock. This modality of assembly calls for the execution of aseries of operations.

In particular, the conductive paths, connected to one another to form asingle body, are positioned inside a mold; next, via injection ofplastic material, co-molding of an intermediate element of pre-setconformation is carried out.

At this point, the blanking operation of the connecting portions of theconductive paths is carried out directly on the intermediate element,which is then positioned inside a further mold for co-molding of thesupporting body of the lock.

In both cases, it is not possible to obtain a supporting body in whichthe conductive paths are arranged on a number of layers set on top ofone another. In fact, in the case where the conductive paths are carriedby the flexible element, the foil conformation of the latter, having aninfinitesimal thickness, in itself prevents the possibility ofgenerating layers of conductive paths set on top of one another.

In the other case, the supporting and positioning close together of anumber of layers of conductive paths inside the mold in which theinjection of the plastic material is performed proves to be practicallyunrealizable, on account of the small thickness of the body that isformed.

The impossibility of obtaining multilayer conductive paths within thesupporting body of the lock can become a markedly penalizing limit aboveall as the number of functions performed by the lock itself, and,consequently, the total number of paths necessary, increases. The use ofsingle-layer paths cannot but entail a high encumbrance and complexityof the electrical control circuit, with obvious negative repercussionson the extension of the supporting body that is designed to house thecircuit.

The purpose of the present invention is to provide a method for making asupporting body for the lock of a motor vehicle which will enable, in asimple and economically advantageous way, the drawbacks related to theknown methods and specified above to be overcome.

SUMMARY OF THE INVENTION

The aforesaid purpose is achieved by the present invention, in so far asit relates to a method for making a supporting body for the lock of amotor vehicle, comprising the steps of:

-   -   forming an intermediate element made of electrically insulating        material provided with conductive paths;    -   setting the intermediate element provided with conductive paths        within a mold to form the supporting body; and    -   injecting electrically insulating material in the mold for        carrying out co-molding of the supporting body;        the method being characterized in that the intermediate element        and the conductive paths are obtained independently, and in that        the conductive paths are fixed to the intermediate element by        constraint means of a mechanical type.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the present invention, there is nowdescribed a preferred embodiment, purely by way of non-limiting example,with reference to the attached drawings, in which:

FIG. 1 is a perspective view of a supporting body for the lock of amotor vehicle, made according to the method forming the subject of thepresent invention;

FIG. 2 is an exploded perspective view of an intermediate elementobtained in the course of the method forming the subject of the presentinvention;

FIG. 3 is a view from beneath the intermediate element of FIG. 2;

FIG. 4 is a view from above the intermediate element of FIG. 2;

FIG. 5 is a cross-sectional view according to the line V-V of FIG. 4;

FIG. 6 is a cross-sectional view similar to that of FIG. 5 representingthe intermediate element in the assembly step; and

FIGS. 7 and 8 are cross-sectional views of the intermediate element ofFIG. 2 and of the supporting body of FIG. 1 during distinct steps of themethod forming the subject of the invention.

DETAILED DESCRIPTION OF THE INVENTION

With reference to FIG. 1, designated, as a whole, by 1 is a supportingbody for the lock of a motor vehicle (in itself known and notillustrated).

The supporting body 1 is constituted by a plate element made of plasticmaterial having a thickness smaller than the other dimensions anddesigned to support and house, in a way known and not illustrated, aplurality of mechanical members, for example levers, one or moreelectric motors of actuating the aforesaid mechanical members, and aplurality of detection members of an electromechanical type, for examplemicroswitches.

The supporting body 1 houses, moreover, an electrical circuit 2 forconnection of the aforesaid detection members and motors to anelectrical connector 14, which can be connected, in turn, in a way knownand not illustrated, to the electrical wiring system of the motorvehicle and which has an external casing made of a single piece with thesupporting body 1 itself.

The circuit 2 is formed by a plurality of conductive paths 3, which, inuse, are independent of one another.

According to an important characteristic of the present invention, theconductive paths 3 are co-molded with the supporting body 1 using themethod described hereinafter and are arranged according to a pluralityof layers set on top of one another, in the case in point three,designated respectively by the reference numbers 4, 5 and 6.

In particular, each layer 4, 5, 6 of conductive paths 3 is made of asingle body in a conventional way by means of operations of blanking andbending conducted on a strip of metal material in the form of a plate,generally copper or brass.

At the end of above operations, the conductive paths 3 of each layer 4,5, 6 are joined together by connecting portions 7 (FIG. 2), designed tobe subsequently removed to enable correct operation of the electricalcircuit 2.

Simultaneously, and in a way independent of the conductive paths 3, anintermediate element 8 made of insulating material, preferably plasticmaterial, is obtained by molding. As may be seen in FIGS. 2 to 4, theintermediate element 8 has a plate conformation and is provided, onopposite faces 9, 10 of its own, of respective pluralities of seats 11,12 for receiving the conductive paths 3.

The intermediate element 8 is further provided with a plurality of pins15 (FIGS. 2 to 6) projecting in cantilever fashion from the faces 9, 10and designed to engage respective through holes 16 having acomplementary shape, made on the conductive paths 3.

Fixing of the layers 4, 5 and 6 of conductive paths 3 on theintermediate element 8 is performed on both of the opposed faces 9, 10of the intermediate element 8 itself.

More precisely, according to a preferred embodiment of the presentinvention, each layer 4, 5, 6 of conductive paths 3, joined together bythe connecting portions 7, is brought close to the corresponding face 9,10 of the intermediate element 8, by coupling the pins 15 with therespective holes 16.

At this point (see FIGS. 5 and 6), by means of thrust members 18 of atype known and illustrated only schematically, the pins 15 are coldpressed to the corresponding face 9, 10 of the intermediate element 8 soas to obtain the riveting of the conductive paths 3 on the intermediateelement 8 itself.

The connecting portions 7 that join the conductive paths 3 of each layer4, 5, 6 are then removed by means of a blanking operation by arrangingthe intermediate element 8 provided with the paths 3 themselves inside apurposely provided mold (in itself known and not illustrated).

Alternatively, the conductive paths 3 of each layer 4, 5, 6 could beseparated from one another, for example manually, prior to their fixingon the intermediate element 8.

In the case in point illustrated, the layers 4 and 5 of conductive pathsare fixed to the face 9 of the intermediate element 8, whilst the layer6 is fixed to the opposite face 10.

The intermediate element 8, which is provided with the conductive paths3, is, at this point, introduced within a cavity 20 formed between twohalf-elements 21, 22 of a mold 23 for carrying out an operation ofco-molding of the supporting body 1 (FIGS. 7 and 8).

Via injection of plastic material within the cavity 20, forming of thesupporting body 1 is carried out, within which there remain embedded theintermediate element 8 and the conductive paths 3 arranged according tothree layers 4, 5, 6 set on top of one another.

From an examination of the characteristics of the method and thesupporting body 1 according to the present invention, the advantagesthat it enables are evident.

In particular, the method previously described enables fabrication of asupporting body 1 for a lock incorporating inside it, within the limitsimposed by its own reduced thickness, a plurality of conductive paths 3arranged according to layers 4, 5, 6 set on top of one another.

The supporting body 1 thus obtained proves particularly suited forhousing locks that implement a large number of electrical functions,without any substantial negative repercussions on its own overalldimensions.

Finally, it is clear that modifications and variations may be made tothe method and the supporting body 1 described and illustrated hereinwithout thereby departing from the scope of protection of the presentinvention.

1. An assembly comprising: a supporting element; an intermediate elementembedded within said supporting element, said intermediate elementhaving opposing faces each including a plurality of seats; and first andsecond layers of conductive paths, said first layer of conductive pathsfixed to one of said opposing faces of said intermediate element andreceived within said plurality of seats thereof, said second layer ofconductive paths fixed to the other of said opposing faces of saidintermediate element and received within said plurality of seatsthereof; wherein each of said first and second layers of conductivepaths are fixed to only one of said opposing faces of said intermediateelement.
 2. The assembly as set forth in claim 1 including a third layerof conductive paths, said third layer of conductive paths fixed to saidintermediate element on the same face as said second layer of conductivepaths.
 3. The assembly as set forth in claim 1 wherein said intermediateelement includes a pin extending out from each of said opposing faces.4. The assembly as set forth in claim 3 wherein each of said first andsecond layers includes a hole for receiving said pin therethrough.